The present invention relates to a safety device for a power tool, and relates particularly, but not exclusively, to an actuator assembly for preventing unintended actuation of a hedge trimmer, and to a power tool incorporating such an assembly.
Hedge trimmers are power tools for general garden use with an axially reciprocating blade comprising a plurality of teeth disposed adjacent a stationary blade, the teeth of the stationary blade providing a reaction force for the teeth of the reciprocating blade.
Most hedge trimmers are provided with two handles for a user to grip. This is generally for two reasons. Firstly, a hedge trimmer is easier to manipulate when held with both hands than when held with one hand. This provides the user with greater control over the hedge trimmer and therefore facilitates more accurate cutting. Secondly, a two handed grip is a safety feature. It is significantly easier to lose control of a hedge trimmer when holding it with one hand, and therefore a two handed grip allows much safer use of the hedge trimmer.
It is known to provide a safety mechanism for a hedge trimmer in which electrical switches for actuating the hedge trimmer motor are connected to both handles, so that the trimmer motor can only be actuated when both handles are held by the user. This prevents one-handed use of the hedge trimmer. However, hedge trimmers which can be actuated using one hand only are sometimes available, and such hedge trimmers suffer from the drawback that accidents may occur as a result of inadvertent one-handed actuation of the hedge trimmer.
Preferred embodiments of the present invention seek to overcome the above disadvantage of the prior art.